Methods and apparatus for spin welding thermoplastic workpieces

Claim 2

Apparatus for spin welding thermoplastic workpieces together comprising: securing means for holding one thermoplastic workpiece, with another thermoplastic workpiece mounted on said one workpiece; gripping means having radially openable and closable jaws forming a recess in which said other workpiece can be positioned; said recess, in the opened condition of said jaws, being of sufficient radial and axial size to prevent any axial or radial contact between said gripping means and said other workpiece when the latter is positioned therein; means continuously rotating said jaws in both the opened and closed positions of said jaws; and power means operable independently of contact between said gripping means and said other workpiece for radially closing said rotating jaws rapidly into radial contact with said other workpiece to rotate said other workpiece substantially instantaneously at the speed of said gripping means and relative to said one workpiece to frictionally melt the interface between said workpieces, and for subsequently releasing said other workpiece from said gripping means.

Claim 3

Apparatus according to claim 1 wherein said jaws rotate about a horizontal axis.

Claim 4

Apparatus according to claim 1 wherein said gripping means comprises a collet reciprocably mounted within a head, said collet including said jaws; which are radially flexible; said power means comprising means for reciprocating said collet relative to said head so that contact between surfaces on said jaws and head flexes said jaws radially inwardly.

Claim 5

Apparatus according to claim 1 including a mandrel mounted on said gripping means and projecting through and outwardly beyond said recess, said mandrel being receivable within a bore of said other workpiece to guide the latter into said recess and being of a length to extend beyond said radial shoulders to prevent melt from said shoulders from blocking said bore.

Claim 6

Apparatus according to claim 4 wherein said mandrel is freely rotatably mounted relative to said rotating collet.

Claim 7

Apparatus according to claim 4 wherein said mandrel is axially displaceable by engagement of a lip thereof with said other workpiece, and means for yieldably resisting such axial displacement to insure that said radial shoulders on said workpieces abut.

Claim 8

Apparatus according to claim 6 wherein said yieldable resisting means comprises a spring.

Claim 9

Apparatus according to claim 1 wherein said securing means comprises a reciprocable non-rotatable clamp means, and power means for reciprocating said clamp means relative to said gripping means.

Claim 10

Apparatus according to claim 8 wherein said clamp means includes a rotatable lever spaced from a clamping recess of said clamp means for serving as a stop for said one workpiece to position said one workpiece in said clamp.

Claim 11

Apparatus according to claim 8 wherein said power means for closing said jaws comprises a power unit connected to said gripping means, switch means for actuating said power unit; said clamp means including an adjustable arm for actuating said switch means when said clamp means is shifted toward said gripping means.

Claim 12

Apparatus according to claim 8 wherein said clamp means comprises a carriage, a pair of movable clamp elements on said carriage, and power means carried by said carriage for opening and closing said clamp elements.

Claim 13

Apparatus according to claim 11 wherein said carriage carries a switch for activating said last named power means, and a movable lever for actuating said last named switch means.

Claim 14

Apparatus for spin welding a thermoplastic socketed fitting to a thermoplastic tube so that bores in said tube and fitting are aligned, said fitting and tube including abutable radial shoulders surrounding said bores, said apparatus comprising: a non-rotatable clamp for securing said tube against rotation, with said fitting being mounted by friction fit on a forward end of said tube; a continuously rotating collet having radially closable jaws which define a recess; an axially movable mandrel extending beyond said recess toward said clamp; means for converging said clamp and said collet so that said mandrel loosely enters the bore of said fitting and said fitting enters said recess; said mandrel having a lip for engagement by said fitting so that said mandrel is urged inwardly; yieldable means resisting axial movement of said mandrel to insure that said radial shoulder of said tube abuts said radial shoulder of said fitting, and power means for suddenly closing said jaws radially into engagement with an outer wall of said fitting to substantially instantly rotate said fitting at the speed of said collet relative to said tube to melt the interface therebetween, and for subsequently releasing said fitting from said jaws.

Claim 15

Apparatus for spin welding a thermoplastic socketed fitting to a thermoplastic tube so that bores in said tube and fitting are aligned, said fitting and tube including abutable radial shoulders surrounding said bores, said apparatus comprising: a non-rotatable clamp for securing said tube against rotation, with said fitting being mounted by friction fit on a forward end of said tube; a continuously rotating collet having radially closable jaws which define a recess; an axially movable mandrel extending beyond said recess toward said clamp; means for converging said clamp and said collet so that said mandrel loosely enters the bore of said fitting and said fitting enters said recess; said mandrel having a lip for engagement by said fitting so that said mandrel is urged inwardly; yieldable means resisting axial movement of said mandrel to insure that said radial shoulder of said tube abuts said radial shoulder of said fitting, and power means for suddenly closing said jaws radially into engagement with an outer wall of said fitting to substantially instantly rotate said fitting at the speed of said collet relative to said tube to melt the interface therebetween, and for subsequently releasing said fitting from said jaws.

Claim 16

Apparatus according to claim 13 wherein said collet rotates about a horizontal axis.

Claim 17

Apparatus according to claim 13 wherein said collet is reciprocably mounted within a head, said power means comprising means for reciprocating said collet inwardly relative to said head so that contact between surfaces on said jaws and head forces said jaws radially inwardly.

Claim 18

Apparatus according to claim 13 wherein said mandrel is of a length to extend beyond the radial shoulders of said tube and fitting to prevent melt from such shoulders from blocking the bores of the tube and fitting.

Claim 19

Apparatus according to claim 13 wherein said mandrel is freely rotatably mounted relative to said collet.

Claim 20

Apparatus according to claim 13 wherein said clamp is reciprocable, and power means are mounted to said clamp for reciprocating said clamp relative to said collet.

Claim 21

Apparatus according to claim 13 wherein said clamp includes a rotatable lever spaced from a clamping recess of said clamp to serve as a stop for said tube to position said tube at a selected distance from said gripping means.

Claim 22

Apparatus according to claim 13 wherein said clamp comprises a carriage, a pair of movable clamp elements on said carriage, and power means carried by said carriage for opening and closing said clamp elements.

Claim 23

Apparatus according to claim 13 wherein said power means for closing said jaws comprises a power unit connected to said collet, switch means for actuating said power unit; said clamp including an adjustable arm for actuating said switch means when said clamp is shifted toward said collet.

Claim 24

Apparatus for spin-welding a pair of thermoplastic workpieces, a first of said workpieces having a socket for receiving a second of said workpieces so that bores of said workpieces are aligned, said first workpiece having a radial shoulder for contacting a radial shoulder of said second workpiece said shoulders surrounding said bores, said apparatus comprising: a horizontally reciprocable carriage, said carriage carrying: a pair of movable clamp elements for receiving said second workpiece and fixing the latter against rotation, power means for opening and closing said clamp elements, power means for reciprocating said carriage, with said second workpiece positioned by friction fit in the socket of said first workpiece; a spinner assembly comprising: a reciprocable collet having radially flexible jaws defining a recess, a head mounted around said collet and having an inclined surface, means for continuously rotating said collet; a mandrel mounted within said collet so as to be axially movable and rotatable relative thereto, said mandrel extending co-axially relative to said collet and projecting through and beyond said recess to be loosely received within a bore of said first workpiece when said clamping means is advanced toward said spinner assembly; said mandrel having a lip to be engaged by said first workpiece; a yieldable spring for resisting axial movement of said mandrel to bring said radial shoulders of said workpieces into abutting relation; means for reciprocating said collet relative to said head to bring said inclined surface into contact with said jaws and flex the latter radially inwardly against said first workpiece so that said first workpiece spins with said collet relative to said second workpiece to melt the interface between said workpieces.

Claim 25

Apparatus for spin-welding a pair of thermoplastic workpieces, a first of said workpieces having a socket for receiving a second of said workpieces so that bores of said workpieces are aligned, said first workpiece having a radial shoulder for contacting a radial shoulder of said second workpiece said shoulders surrounding said bores, said apparatus comprising: a horizontally reciprocable carriage, said carriage carrying: a pair of movable clamp elements for receiving said second workpiece and fixing the latter against rotation, power means for opening and closing said clamp elements, power means for reciprocating said carriage, with said second workpiece positioned by friction fit in the socket of said first workpiece; a spinner assembly comprising: a reciprocable collet having radially flexible jaws defining a recess, a head mounted around said collet and having an inclined surface, means for continuously rotating said collet; a mandrel mounted within said collet so as to be axially movable and rotatable relative thereto, said mandrel extending co-axially relative to said collet and projecting through and beyond said recess to be loosely received within a bore of said first workpiece when said clamping means is advanced toward said spinner assembly; said mandrel having a lip to be engaged by said first workpiece; a yieldable spring for resisting axial movement of said mandrel to bring said radial shoulders of said workpieces into abutting relation; means for reciprocating said collet relative to said head to bring said inclined surface into contact with said jaws and flex the latter radially inwardly against said first workpiece so that said first workpiece spins with said collet relative to said second workpiece to melt the interface between said workpieces.

Claim 28

A method according to claim 23 wherein said positioning step comprises positioning within a bore of said first workpiece a mandrel which projects from said gripping member and extends axially beyond said jaws.

Claim 31

A method according to claim 25 wherein said jaws rotate relative to said mandrel, and said mandrel enters said bore and extends axially beyond the juncture of said radial shoulders to prevent melt from said shoulders from closing said bore.

Claim 32

Apparatus for spin welding thermoplastic workpieces together comprising: securing means for holding one thermoplastic workpiece, with another thermoplastic workpiece mounted on said one workpiece; gripping means having radially closable jaws forming a recess in which said other workpiece can be located; a mandrel mounted on said gripping means and projecting through and outwardly beyond said recess, said mandrel being receivable within a bore of said other workpiece to guide the latter into said recess and being of a length to extend beyond said radial shoulders to prevent melt from said shoulders from blocking said bore; means for continuously rotating said jaws; and power means for radially closing said rotating jaws rapidly into radial contact with said other workpiece to rotate said other workpiece substantially instantaneously at the speed of said gripping means and relative to said one workpiece to frictionally melt the interface between said workpieces, and for subsequently releasing said other workpiece from said gripping means.

Claim 33

Apparatus for spin welding thermoplastic workpieces together comprising: securing means for holding one thermoplastic workpiece, with another thermoplastic workpiece mounted on said one workpiece; gripping means having radially closable jaws forming a recess in which said other workpiece can be located; a mandrel mounted on said gripping means and projecting through and outwardly beyond said recess, said mandrel being receivable within a bore of said other workpiece to guide the latter into said recess and being of a length to extend beyond said radial shoulders to prevent melt from said shoulders from blocking said bore; means for continuously rotating said jaws; and power means for radially closing said rotating jaws rapidly into radial contact with said other workpiece to rotate said other workpiece substantially instantaneously at the speed of said gripping means and relative to said one workpiece to frictionally melt the interface between said workpieces, and for subsequently releasing said other workpiece from said gripping means.

Claim 34

Apparatus for spin welding thermoplastic workpieces together comprising: a reciprocable nonrotatable clamp for holding one thermoplastic workpiece, with another thermoplastic workpiece mounted on said one workpiece; said clamp including a movable arm spaced from said clamping recess for serving as a stop for said one workpiece to position the latter in said clamp; gripping means having radially closable jaws forming a recess in which said other workpiece can be located; first power means for reciprocating said clamp relative to said gripping means to position said other workpiece in said recess; means for continuously rotating said jaws; and second power means for radially closing said rotating jaws rapidly into radial contact with said other workpiece to rotate said other workpiece substantially instantaneously at the speed of said gripping means and relative to said one workpiece to frictionally melt the interface between said workpieces, and for subsequently releasing said other workpiece from said gripping means.

Claim 35

Apparatus for spin welding thermoplastic workpieces together comprising: a reciprocable nonrotatable clamp for holding one thermoplastic workpiece, with another thermoplastic workpiece mounted on said one workpiece; said clamp including a movable arm spaced from said clamping recess for serving as a stop for said one workpiece to position the latter in said clamp; gripping means having radially closable jaws forming a recess in which said other workpiece can be located; first power means for reciprocating said clamp relative to said gripping means to position said other workpiece in said recess; means for continuously rotating said jaws; and second power means for radially closing said rotating jaws rapidly into radial contact with said other workpiece to rotate said other workpiece substantially instantaneously at the speed of said gripping means and relative to said one workpiece to frictionally melt the interface between said workpieces, and for subsequently releasing said other workpiece from said gripping means.

Claim 36

Apparatus for spin welding thermoplastic workpieces together comprising: a reciprocable nonrotatable clamp for holding one thermoplastic workpiece, with another thermoplastic workpiece mounted on said one workpiece; gripping means having radially closable jaws forming a recess in which said other workpiece can be located; first power means for reciprocating said clamp relative to said gripping means to position said other workpiece in said recess; means for continuously rotating said jaws; second power means for radially closing said rotating jaws rapidly into radial contact with said other workpiece to rotate said other workpiece substantially instantaneously at the speed of said gripping means and relative to said one workpiece to frictionally melt the interface between said workpieces, and for subsequently releasing said other workpiece from said gripping means, said second power means comprising: a power unit connected to said gripping means, and switch means for actuating said power unit, and an arm mounted for movement with said clamp for actuating said switch means when said clamp is shifted toward said gripping means.

Claim 37

Apparatus for spin welding thermoplastic workpieces together comprising: a reciprocable nonrotatable clamp for holding one thermoplastic workpiece, with another thermoplastic workpiece mounted on said one workpiece; gripping means having radially closable jaws forming a recess in which said other workpiece can be located; first power means for reciprocating said clamp relative to said gripping means to position said other workpiece in said recess; means for continuously rotating said jaws; second power means for radially closing said rotating jaws rapidly into radial contact with said other workpiece to rotate said other workpiece substantially instantaneously at the speed of said gripping means and relative to said one workpiece to frictionally melt the interface between said workpieces, and for subsequently releasing said other workpiece from said gripping means, said second power means comprising: a power unit connected to said gripping means, and switch means for actuating said power unit, and an arm mounted for movement with said clamp for actuating said switch means when said clamp is shifted toward said gripping means.

Claim 38

Apparatus for spin welding thermoplastic workpieces together comprising: a reciprocable nonrotatable clamp for holding one thermoplastic workpiece, with another thermoplastic workpiece mounted on said one workpiece; said clamp comprising a carriage, a pair of movable clamp elements on said carriage, and first power means carried by said carriage for opening and closing said clamp elements; gripping means having radially closable jaws forming a recess in which said other workpiece can be located; first power means for reciprocating said clamp relative to said gripping means to position said other workpiece in said recess; means for continuously rotating said jaws; and second power means for radially closing said rotating jaws rapidly into radial contact with said other workpiece to rotate said other workpiece substantially instantaneously at the speed of said gripping means and relative to said one workpiece to frictionally melt the interface between said workpieces, and for subsequently releasing said other workpiece from said gripping means.

Claim 39

Apparatus for spin welding thermoplastic workpieces together comprising: a reciprocable nonrotatable clamp for holding one thermoplastic workpiece, with another thermoplastic workpiece mounted on said one workpiece; said clamp comprising a carriage, a pair of movable clamp elements on said carriage, and first power means carried by said carriage for opening and closing said clamp elements; gripping means having radially closable jaws forming a recess in which said other workpiece can be located; first power means for reciprocating said clamp relative to said gripping means to position said other workpiece in said recess; means for continuously rotating said jaws; and second power means for radially closing said rotating jaws rapidly into radial contact with said other workpiece to rotate said other workpiece substantially instantaneously at the speed of said gripping means and relative to said one workpiece to frictionally melt the interface between said workpieces, and for subsequently releasing said other workpiece from said gripping means.